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The Permo-Carboniferous Schmidgaden, Weiden, Erbendorf and Stockheim basins from southern Germany host discontinuous seams of high ash coal and carbargillites which were mined for hard coal, explored for uranium and only recently have proved their source rock potential for gaseous and fluid hydrocarbons. Alteration and facies of these carbonaceous beds were geologically and chemically investigated. During silicification which is exclusively confined to the carbonaceous interbeds of pyroclastic depositions, element depletion prograded except for Zn, Pb, U. The anoxic environments under consideration may be subdivided into fluvial/swamp (Upper Westphalian beds from Schmidgaden, Weiden, Erbendorf and Stockheim) and lacustrine depositions (Upper Stephanian and Upper Autunian carbargillites from Erbendorf, Weiden-Bechtsrieth). SiO2, MgO, CaO, Mo and Zr have proved to be most suitable for recognition of these environments, whereas, U, K2O and notably Cu/Zn are less appropriate. In the ternary plots displaying the organic chemistry of extracts of these carbonaceous beds fluvial swamps have low and lacustrine beds high contents of saturated hydrocarbons. All samples show a pronounced OEP (=odd even predominance) of n-alkanes which partly are environment-controlled (terrestrial origin), partly maturity-controlled. The high iso- and cyclo-alkanes of Schmidgaden and bimodal n-alkyl distribution point to a contribution of algal material. Finally four basin types bearing carbonaceous rocks are discussed with respect to their economic potential and compared with basins elsewhere (Cerilly, Lodève, St. Hippolyte, Uinta): type I: intramontane fault-bounded basin (swamp), type II: volcanic-depression with steep relief (swamps), type III: halfgraben (lake), type IV: volcanic-depression with smooth relief (lake). Types I and II are of interest for hard coal, organic-hosted U-deposits and mainly gasprone; types III and IV, however, show good source-rock potential for crude oil. 相似文献
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Manfred Teschner Eckhard Faber Jürgen Poggenburg Georgios E. Vougioukalakis Georgios Hatziyannis 《Pure and Applied Geophysics》2007,164(12):2549-2571
In this paper the installation and long-term operation of a system for continuous monitoring of fumarolic gases is described.
Several physicochemical and gas-geochemical parameters such as the concentration of CO2, H2S and CO in the fumarolic emissions, as well as the temperatures of the hydrothermal steam and soil in close vicinity of the
fumarole and steam pressure are measured in short-time intervals (typically 15 seconds). Data are logged on-site and in parallel
transferred to a remote station by digital telemetry. Specially developed software enables the real-time observation of the
local conditions in the crater and full bidirectional control of the monitoring system. Fluctuations in the monitored parameters
are also reported. From the data presented it can be concluded that environmental conditions (direction and strength of wind,
precipitation) will interact with some of the parameters monitored. These influences can only be revealed by continuously
operated monitoring systems. 相似文献
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Na’ama Teschner 《Urban geography》2013,34(7):918-937
ABSTRACTThe zone of intersection between land and sea within an urban context has long been viewed as a special type of urban commons. The well-researched port-city interface, however, tells a rather tragic story about the use and management of this valuable resource. This study asks how four major regulatory-institutional issues in the interface – land ownership, activities allowed in port area, planning autonomy, and public access – affect the ability of ports and cities to preserve elements of “commons” in urban coasts? Furthermore, it assesses if and how Elinor Ostrom’s principles for overcoming commons-related tensions, could contribute to the management of port-city conflicts over land-uses in the Mediterranean urban coastline and the various questions that may derive from such an application. For these purposes the study combines a comprehensive literature review with the analysis of planning regulation and in-depth, semi-structured interviews of key-stakeholders in seven port cities across three Mediterranean countries. The common experience in these different cases suggests that through a strategy involving scaling-down spatial decisions or governance, and built-in mechanisms for spatial cooperation, ports and the cities that host them can find a new joint path, which will strengthen local synergies and the quality of urban, public space. 相似文献
4.
Falk H. Weinlich Eckhard Faber Alena Boukov Josef Horlek Manfred Teschner Jürgen Poggenburg 《Tectonophysics》2006,421(1-2):89-110
A continuously operated gas monitoring station was emplaced within the epicentral area of the NW Bohemian swarm earthquakes overlying directly the active Mariánské Lázně fault. The recordings of 8-month continuous monitoring period are presented. The variations in radon concentrations are similarly to variations in CO2, i.e. CO2 is considered to be the carrier gas for radon. Very small diurnal variations in gas concentration are caused by the earth tides, as daily variations in meteorological conditions cannot explain a short daily minimum at midday times. Sudden changes in gas concentration, which clearly exceed these diurnal variations occur and are always linked with seismic activities. Decreased gas concentration may indicate compression resulting in reduced fault permeability as is implied by negative peaks following local earthquake swarms. A sudden increase in CO2 and Rn concentration may indicate an increased fault permeability caused by stress redistribution, giving rise to opening of migration pathways. This implies a repeatedly sudden rise in gas concentration before local earthquake swarms. Several variations in gas concentration were monitored linked with remote earthquakes of ground motion amplitudes >1 μm. These seismic events are accompanied by an interference of the diurnal gas concentration–stress-cycle along the Mariánské Lázně fault. However, if shocks of remote earthquake can alter properties of the migrating fluids or the fault properties it can be suggested that these are able to trigger local seismicity, as indicated in the case of the Slovenia earthquake on 12th July 2004. 相似文献
5.
Continuous gas monitoring in the West Bohemian earthquake area,Czech Republic: First results 总被引:1,自引:1,他引:0
Eckhard Faber Josef Horálek Alena Boušková Manfred Teschner Ulrich Koch Jürgen Poggenburg 《Studia Geophysica et Geodaetica》2009,53(3):315-328
Two stations monitoring concentrations of carbon dioxide and radon in soil gas (Oldřišská and Novy Kostel) and one station
monitoring flow of carbon dioxide at a mofette (Soos) have been operated in the area of the West Bohemian earthquake swarms.
We present preliminary results obtained on the base of four-year observations. We found that data are not influenced considerably
by barometric pressure. Although the CO2 concentration varies greatly, the long-term trends at stations Oldřišská and Novy Kostel are similar, which indicates that
the CO2 flow is controlled by common geogenic processes. Also temporal trends of CO2 and Rn concentrations in soil gas at individual stations are analogous. We found diurnal variations of both CO2 concentration in soil gas and the CO2 flow at mofettes due to the earth tides. A response to tides of semi-diurnal period is insignificant in CO2 concentration and only weak in the CO2 flow. We also examined possible pre-seismic, co-seismic and post-seismic effects of the intensive 2008 earthquake swarm on
the CO2 concentration at Oldřišská and Novy Kostel, and on the CO2 flow at Soos. However, all potential indications were insignificant and there has not been proven any influence of the swarm
on the CO2 concentration as well as on the CO2 flow. Nevertheless, a gradual decrease of amplitudes of diurnal variations before the swarm and the lowest amplitudes during
the swarm is a noteworthy phenomenon, which might indicate the strain changes of the rock associated with earthquake swarm. 相似文献
6.
W. Teschner 《Celestial Mechanics and Dynamical Astronomy》1980,21(3):311-320
Optimality conditions for intermediate-thrust arcs (IT-arcs) of rocket trajectories in rotating potential force fields where Coriolis-forces have to be taken into account are derived. For coplanar problems, the existence of IT-arcs in optimal time-free transfers depends on inequality conditions, based mainly on properties of the local potential field. Therefore, the region of the potential force field, where no time-free optimal IT-arc exists, can easily be evaluated. As an example the restricted three-body problem will be considered. 相似文献
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Ulrych Jaromír Krmíček Lukáš Teschner Claudia Řanda Zdeněk Skála Roman Jonášová Šárka Fediuk Ferry Adamovič Jiří Pokorný Richard 《Mineralogy and Petrology》2017,111(5):761-775
Mineralogy and Petrology - Tachylytes from rift-related volcanic rocks were recognized as: (i) irregular veinlets in host alkaline lava flows of the Kozákov volcano, Czech Republic, (ii)... 相似文献
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T.?GüntherEmail authorView authors OrcID profile K.?M.?Haase R.?Klemd C.?Teschner 《Contributions to Mineralogy and Petrology》2018,173(6):51
We report a new whole-rock dataset of major and trace element abundances and 87Sr/86Sr–143Nd/144Nd isotope ratios for basaltic to rhyolitic lavas from the Rooiberg continental large igneous province (LIP). The formation of the Paleoproterozoic Rooiberg Group is contemporaneous with and spatially related to the layered intrusion of the Bushveld Complex, which stratigraphically separates the volcanic succession. Our new data confirm the presence of low- and high-Ti mafic and intermediate lavas (basaltic—andesitic compositions) with >?4 wt% MgO, as well as evolved rocks (andesitic—rhyolitic compositions), characterized by MgO contents of <?4 wt%. The high- and low-Ti basaltic lavas have different incompatible trace element ratios (e.g. (La/Sm)N, Nb/Y and Ti/Y), indicating a different petrogenesis. MELTS modelling shows that the evolved lavas are formed by fractional crystallization from the mafic low-Ti lavas at low-to-moderate pressures (~?4 kbar). Primitive mantle-normalized trace element patterns of the Rooiberg rocks show an enrichment of large ion lithophile elements (LILE), rare-earth elements (REE) and pronounced negative anomalies of Nb, Ta, P, Ti and a positive Pb anomaly. Unaltered Rooiberg lavas have negative εNdi (??5.2 to ??9.4) and radiogenic εSri (6.6 to 105) ratios (at 2061 Ma). These data overlap with isotope and trace element compositions of purported parental melts to the Bushveld Complex, especially for the lower zone. We suggest that the Rooiberg suite originated from a source similar to the composition of the B1-magma suggested as parental to the Bushveld Lower Zone, or that the lavas represent eruptive successions of fractional crystallization products related to the ultramafic cumulates that were forming at depth. The Rooiberg magmas may have formed by 10–20% crustal assimilation by the fractionation of a very primitive mantle-derived melt within the upper crust of the Kaapvaal Craton. Alternatively, the magmas represent mixtures of melts from a primitive, sub-lithospheric mantle plume and an enriched sub-continental lithospheric mantle (SCLM) component with harzburgitic composition. Regardless of which of the two scenarios is invoked, the lavas of the Rooiberg Group show geochemical similarities to the Jurassic Karoo flood basalts, implying that the Archean lithosphere strongly affected both of these large-scale melting events. 相似文献
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